1. Field of the Invention
The present invention is related to a single-conductor positioning device on each or either lateral side of a bulb holder, and especially to such a device capable of firmly positioning a single conductor at a central position on each or either lateral side of the bulb holder.
2. Description of the Prior Art
Conventional decorative lamps are mostly in the form of strings each having multiple lamp bulbs connected to a conductor; modern decorative lamps of such kind are arranged in a plane in the form of a net, thereby conventional lamp strings were developed to have the plane decorative function.
Early decorative lamps in the form of nets, such as that in the U.S. Pat. No. 5,662,409 owned by the applicant of the present application, must have multiple lamp bulbs positioned at different locations on the entire network, hence locking members are required to secure every lamp bulb on the net formed by conductor for the lamp bulbs.
Using the locking members on decorative lamps in the form of nets to position multiple lamp bulbs not only is inconvenient in construction, but also is uneconomic. In view of this, modern decorative lamps in the form of nets have for each bulb holder a conductor-positioning device integrally formed therewith to save the abovementioned locking members additionally provided. Such an integrally formed conductor-positioning device was disclosed in U.S. Pat. Nos. 5,839,819, 5,908,238 and 6,116,951.
In the U.S. Pat. No. 5,839,819 as an example, a connecting base is integrally formed on a lateral side of the bulb holder; the connecting base has an outward groove, thereby, the conductor for the lamp bulbs can be placed in the connecting base through the groove. Although the patent has the advantage of omitting a locking member additionally provided and fast positioning on the conductor, the front face of the outward groove faces to the lateral side of the bulb holder, thereby, when the decorative lamps in the form of a net is pulled sideways, the outwardly facing direction of the groove for clamping therein the conductor is coincident with the direction of stretching of the net light. In this mode, the bulb holder and its lamp bulb are much subjected to getting off their positions when the conductors are exerted with pulling force. Thereby, the whole net light looses its static or dynamic flashing or illuminating patterns previously set. Such a connecting base with the outward groove on the lateral side totally opened is subjected to pulling sideways and thus lack of the ability of sure positioning the conductor.
The U.S. Pat. No. 6,116,951 also provided a conductor clamping device for such a net light; wherein, the bulb holders each is also integrally formed with a connecting base merely the same as that of the aforesaid connecting base. The connecting base is provided on a lateral side thereof with a protruding rib which is connected to the connecting base by means of an engagement block; the engagement block is provided with a concave groove matching with the protruding rib. Thereby, the engagement block can synchronically position two conductors passing through the corresponding lamp bulbs and its bulb holders when it is connected to the connecting base.
However, such a net light generally has singular conductors passed through lamp bulbs and their corresponding bulb holders in the process of manufacturing. Positioning of a singular conductor must be very firm to prevent getting off during pulling sideways, and must be accurately positioned at the centers of the lateral sides of the bulb holders. In this mode, fixed assembling of the entire net light can only be assured, and the lamp bulbs can surely be located at the intercrossing points of net lines, such locating can influence the pattern of flashing of the lamp bulbs. The above stated U.S. Pat. No. 5,839,819 is unable to get firm positioning of the conductor; while the U.S. Pat. No. 6,116,951 is evidently hard to suit accurate positioning of the conductor.
The object of the present invention is to provide a single-conductor positioning device on each or either lateral side of a bulb holder; the device is capable of firmly positioning a single conductor at a central position on each or either lateral side of the bulb holder.
To obtain the above stated object, the present invention is provided with a receiving seat integrally formed on each or either lateral side of the bulb holder and comprised of two hook-like sidewalls opposite to each other. A plug can be fitted in an inner slot and a central slit both formed in the receiving seat. In this preferred embodiment, the plug can form together with the inner slot of the receiving seat a conductor clamping-slot; and can further be provided with vertical grooves for connecting with the hooks of the sidewalls of the receiving seat. Thus the phenomenon that the outward groove of a connecting base is subjected to pulling sideways to make a conductor get off its position by a pulling force can be effectively prevented.
In this preferred embodiment, the plug has a base slightly enlarged and used as a limit portion against pushing.
And in another preferred embodiment, the conductor clamping-slot formed by a recess of the plug and the receiving seat is formed to be a conical hole, and has a raised strip.
In another preferred embodiment, the plug can be formed independently a conductor sleeve on the external surface of the receiving seat.
The present invention will be apparent in its novelty and features after reading the detailed description of the preferred embodiment thereof in reference to the accompanying drawings.